Integra Ascension MCP Manual Del Usario página 6

Effectiveness Analysis
(RA/SLE Longer-Term Outcome Evaluation)
To conduct the Longer-Term Outcome Evaluation, the Effectiveness Criteria
for all outcome categories (Excellent, Good, Unsatisfactory, and Indeterminate)
that were established for the 1-5 year evaluation were modified so that
reductions in treatment improvements at evaluation times greater than five (5)
years were considered during implant outcome evaluation . Thus, the
following effectiveness criteria were applied on an implant basis to determine
the treatment outcome category for each implant .
Excellent
1 . Physical exam, ROM data, and radiographic data
> 1 year 2 indicating:
a . Improvement of all treatment objectives;
b . Pain free joint; and
c . Reduced implant position .
Good
1 . Physical exam, ROM data, and radiographic data
< 1 year 2 indicating:
a . Improvement of all treatment objectives;
b . Pain free joint; and
c . Reduced implant position; and
2 . Subjective or objective information (a physical exam at another clinic
(ortho pedic, rheumatolgy, etc . ) , radiographic data, a questionnaire or
telephone conversation with a physician) at > 1 year indicating:
a . maintenance of the improvements; and
b . implant survival .
Unsatisfactory
1 . Primary treatment objective(s) same or not improved by the surgery;
2 . Implant related pain at last evaluation;
3 . Implant loosening;
4 . Implant removal;
5 . Implant dislocation; or
6 . Post-operative implant fracture
Indeterminate
1 . No information > 1 year, or insufficient information
> 1 year to indicate maintenance of the improvements
Effectiveness Results
(RA/SLE Longer-Term Evaluation)
In the RA/SLE cohort, the longer-term evaluation revealed the following:
Table 8. RA/SLE Longer-Term Effectiveness Results.
"Success"
"Failure"
"Indeterminate"
Patients w/ All Implants "Success"
Patients w/ All Implants "Failure"
Patients w/ All Implants "Indeterminate"
Patients w/ multiple Implant Outcomes
("Success" and/or "Failure",
and/or "Indeterminate"
Thirty (30) implant outcomes were considered excellent with a final evaluation
occurring at an average of 7 . 6 years (range 1 . 0 -15 . 9 years) after implantation; 23
of those 30 implants had a final evaluation > 2 years after implan tation .
Twenty-one (21) implant outcomes were considered good with a final
evaluation occurring at an average of 6 . 8 years (range 1 . 3 -16 . 8 ) after
implantation; 11 of those 21 implants had a final evaluation > 2 years after
implan tation . Thus, 34 of the 51 successful implants had a final evaluation
greater than 2 years after implantation, a rate of 67% (34/51) .
Under the modified longer-term criteria, successful implants were in 23 of
the 45 RA/SLE patients, a rate of 51% (23/45) . Of the 23 patients with at least
one successful implant, 17 had all their implants considered successful, a rate
of 74% (17/23) . Therefore, 38% (17/45) of the patients in the RA/SLE cohort had
all their implants considered successful when applying longitudinal
effectiveness criteria .
Implants Patients
(N = 138) (N = 45)
51 (37%)
(30 Excellent, --
21 Good)
73 (53%) --
14 (10%) --
-- 17 (38%)
-- 18 (40%)
-- 3 (7%)
-- 7 (15%)
6
For implants demonstrating excellent and good outcomes, the primary
treatment objectives for all implants were obtained . There were no reports of
implanted joint pain at a final evaluation occurring at an average of 7 . 0 years
(range 1 . 0 -16 . 8 years) after implantation, and no reports of hand or finger pain .
The average extension increase was 33 . 7 degrees (range of –50 to 125 degrees)
with a final evaluation occurring an average of 3 . 3 years (range 0 . 1 -16 . 8 years)
after implantation . All patients with a primary treatment expectation of
increasing extension showed an extension increase . Five implants in 4 patients
with a treatment expectation of joint reduction and/or surface replacement
and/or pain relief showed an extension decrease, but had good to excellent
post-operative range of motion (ROM) averaging 28 . 0 degrees (range 20 to 40
degrees) . Of the 51 implants considered successful, radiographic data showed
43 implants reduced, a rate of 84% (43/51); and 8 implants were subluxed at a
final evaluation occurring an average of 4 . 2 years (range 0 . 1 -13 . 1 years) after
implantation . No successful implants were dislocated in the long-term .
For the group of 73 implants with an unsatisfactory outcome in 25
patients, 20 implants in 10 patients were removed . Two implants were
removed due to loosening (1 at 1 . 5 years and 1 at 4 . 9 years) . The 18 other
removed implants were revised due to disease related soft tissue degradation
that resulted in flexion contracture (8 implants: 2 each in 2 patients and 4 in
another), ulnar deviation deformity and dislocation (3 implants in 1 patient), or
subluxation/dislocation (7 implants: 1 in 1 patient, and 2 each in 3 other
patients) . All removed implants were successfully revised; 15 were replaced
with silicone spacers, 4 Pyrocarbon MCP implants were reinserted with bone
cement, and 1 new Pyrocarbon MCP implant was inserted .
The other 53 implants with an unsatisfactory outcome in 18 patients were
unsuccessful due to extension contracture or flexion lag (13 implants: 1 each in
4 patients, 2 in 1 patient, 3 in 1 patient, and 4 in 1 patient), lack of extension
improvement or extension deficit (27 implants: 4 each in 4 patients, 3 in 1
patient, 2 each in 3 patients, and 1 each in 2 patients), recurrent severe ulnar
deformity (4 in 1 patient), dislocation (7 implants: 4 in 1 patient, 2 in 1 patient,
and 1 in 1 patient), and loss of motion (2 implants in 1) . Thus, of the 73 implants
with unsatisfactory outcome in 25 patients, only 2 were directly related to
implant loosening . All other unsatisfactory outcomes were due to disease
related soft tissue degradation leading to reduction or loss of motion, joint
dislocation, or recurrent ulnar deformity .
Comparison of RA/SLE Effectiveness Results
The impact of applying the modified longer-term effectiveness criteria to
determine effectiveness results for the RA/SLE patient cohort is shown below .
Table 9. RA/SLE 1-5 Year and Longer Term
Effectiveness Results Comparison.
1 - 5 Year Criteria
N
Total 138
82
Excellent & Good
(46 Ex & 36 Gd)
Unsatisfactory 37
Indeterminate 19
When reductions in treatment improvements at evaluation times of greater
than five (5) years are considered, the number of successful implants (excellent
and good outcomes) decreases from 82/138 (59%) to 51/138 (37%), while the
number of implants with unsatisfactory outcome increases from 37/138 (27%)
to 73/138 (53%) . For the 36 additional implants with unsatisfactory outcome,
6 implants were removed from 2 patients (4 from 1 patient at 5 . 4 years due to
flexion contracture and ulnar deviation deformity, and 2 from another patient
at 11 . 0 years due to subluxation/dislocation); all 6 removed implants were
successfully replaced with a silicone spacer . The other 30 additional implants
with unsatisfactory outcome were considered failures due to extension lag (15
implants in 6 patients), flexion lag/stiffness (9 implants in 5 patients),
dislocation (4 implants in 1 patient), and loss of motion (2 implants in 1
patient) . Thus, all 36 additional implants with unsatisfactory outcome under
the modified effectiveness criteria were unsuccessful due to disease related
soft tissue degradation and attenuation leading to reduction or loss of motion,
joint dislocation, or recurrent ulnar deformity .
Safety Analysis (RA/SLE)
The frequency and severity of the following events were evaluated for
purposes of determining device safety:
1 . Intraoperative implant fracture
2 . Non-intraoperative implant fracture
3 . Unstable intraoperative bone fracture
4 . Post operative bone fractures
5 . Implant related infection
6 . Adverse biological reaction to implant
Longer-Term Criteria
% N %
138
51
59% 37%
(30 Ex & 21 Gd)
27% 73 53%
14% 14 10%